The present invention relates to an apparatus and a method of heating plastics material pre-forms. In the field of the plastics-processing industry and, in particular, the drinks-producing industry it has long been known to shape plastic bottles from plastics material pre-forms by blow moulding. In this case these plastics material pre-forms are first heated in a heating device and they are then expanded in this expanded state.
Various heating apparatus are known from the prior art. In this way for example, infrared furnaces are known through which the plastics material pre-forms are conveyed, as well as also microwave furnaces. In the case of heating apparatus of this type it is usual for a plurality of carriers for the individual plastics material pre-forms to be arranged one behind the other on a main carrier. In this case it is desirable for there to be a slight gap between the adjacent plastics material pre-forms in each case.
In addition, apparatus of this type also usually have screening elements which protect the apertures of the plastics material pre-forms—which are not shaped themselves—from excessive heating. In the case of apparatus of this type, however, it is frequently necessary for a change of fittings to be carried out at regular intervals. For this purpose both the holding elements and the aforesaid screening plates are replaced individually, which in some cases is very complicated.
The object of the present invention is therefore to facilitate or make less time-consuming a change of fittings in particular for apparatus of this type for the heating of plastics material pre-forms.